1. Field of the Invention
The present invention relates to a camera having a display member.
2. Description of the Related Art
Conventional cameras have been provided with a finder by which an object in an imaging range is visually recognized and which has a superimposed function providing indexes showing the imaging range, a distance-measuring range and a light-measuring range. Further, in recent years, cameras to which a function for performing most suitable distance-measurement and light-measurement in accordance with situations by setting a plurality of distance-measuring and light-measuring points in a photographing view field is added have been provided. Such cameras notify a photographer the positions of indexes with displaying and non-displaying by switching emitting and non-emitting of the plurality of indexes representing the distance-measuring and light-measuring points in the finder visual field.
However, the conventional superimposed function formed by metal film deposition has had a problem that manufacturing costs are high and quality of visibility is not satisfactory due to occurrence of misalignment of vapor disposition. To attend to the problem, Japanese Patent Application Laid-Open No. 2005-338662 provides a superimposed display method in which a plurality of square frames and a reflective prism group represent positions of distance-measuring and light-measuring points on an optical flat plate, with good visibility and low costs. The reflective prism group is provided with a plurality of reflective prisms on a surface of the optical flat plate opposed to another surface on which the square frames are formed, each reflective prism being formed by a ridge formed by sloped surfaces contacted with each other, sloping in at least two directions, the reflective prism being arranged in such a manner that direction of the ridges thereof being arranged in a same direction.
Further, it is configured that illuminated light from lighting is reflected by a sloped surface to reach a photographer's eye. The reflected light from the reflective prism when lighting is emitted is guided to the photographer's pupil so that the photographer can visually recognize light emission in the finder. On the other hand, when the lighting is not emitted, the photographer can visually recognize as a point a range where the reflective prism group in the finder extends.
On the other hand, to make the photographer recognize an automatic focusing position on the finder, a frame shaped in square or the like is formed on the optical flat plate. For example, it is disclosed that a frame line constituting a frame is shaped in a V-shaped convex in Japanese Patent Application Laid-Open No. 2008-180970. By this structure, light is curved by a sloped surface having the V-shaped convex so that the light does not reach the photographer's eye, thereby the photographer recognizes the V-shaped convex as a black line-like index.
However, there is a problem that a conventional optical flat plate into which Japanese Patent Application Laid-Open No. 2005-338662 and Japanese Patent Application Laid-Open No. 2008-180970 are incorporated together has the flame line inferior in visibility. FIGS. 10A and 10B illustrate a conventional optical flat plate, of which FIG. 10A is a cross sectional view of a frame line and a reflective prism group on an optical flat plate and FIG. 10B is a view illustrating a finder visual field. As illustrated in FIG. 10A, it sometimes occurs that light L from an object is refracted at sloped surfaces 112 and 113 of the reflective prism 111 to pass in the optical flat plate 101, and is refracted at sloped surfaces 115 and 116 of a V-shaped convex 114 to reach a photographer's eye. This phenomenon occurs when a ridge line of the V-shaped convex having a certain height is parallel to a ridge line of the frame line.
FIG. 10B is a view illustrating a frame line in a central region of a right-and-left direction observed in the finder. According to the above-mentioned phenomenon, the light L is guided to the photographer's eye so that an area of the frame line 121 formed by the reflective prism in the frame line is blanked white. Accordingly there has been a problem that a difference in color density in the frame line becomes remarkable so that visibility of the frame line is deteriorated.